1. Field of the Invention
The present general inventive concept relates to a high voltage power supply and a high voltage power control method thereof. More particularly, the present general inventive concept relates to a high voltage power supply, which generates a high voltage power independent of an output load according to a high voltage output setting signal, and a high voltage control method thereof.
2. Description of the Related Art
Generally, a high voltage power supply is used to power an electric device requiring a number of kilo volts (KV) of a high voltage direct current source such as a laser printer and/or a facsimile. The high voltage power supply converts a direct current into a high voltage alternating current (AC), and rectifies the high voltage alternating current to convert the high voltage alternating current into a high voltage direct current (DC). Generally, the high voltage power supply comprises a transformer for converting a direct current into an alternating current.
FIG. 1 is a block diagram illustrating an image forming apparatus including a conventional high voltage power supply 100.
Referring to FIG. 1, the image forming apparatus includes an engine controller 10, a development device 50, and the conventional high voltage power supply 100.
The engine controller 10 controls the high voltage power supply 100 to generate a high voltage power for supplying to the development device 50. Particularly, the engine controller 10 supplies a logic level high signal as a “High/Low” signal and a high voltage power supply (HVPS) control signal to the high voltage power supply 100 only if the high voltage power needs to be output. The engine controller 10 outputs a pulse width modulation signal (PWM 1, PWM 2, . . . , PWM n) with a certain duty ratio according to a preset value to the high voltage power supply 100.
A plurality of the pulse width modulation signals (PWM 1, PWM 2, . . . , PWM n) are used according to the high voltage power that the development device 50 requires, and a plurality of high voltage power supplies of the high voltage power supply 100 are also required according to the plurality of pulse width modulation signals (PWM 1, PWM 2, . . . , PWM n). Accordingly, a plurality of high voltage outputs (HV output 1, HV output 2, . . . , HV output n) are output from the plurality of high voltage power supplies of the high voltage power supply 100.
The high voltage power supply 100 can generate a high voltage power of hundreds to thousands of volts by switching on/off due to the pulse width modulation signals (PWM 1, PWM 2, . . . , PWM n) applied from the engine controller 10. The high voltage power supply 100 outputs the generated high voltage outputs (HV output 1, HV output 2, . . . , HV output n) to the development device 50.
To output the plurality of high voltage outputs (HV output 1, HV output 2, . . . , HV output n), the engine controller 10 generates the plurality of the pulse width modulation signals (PWM 1, PWM 2, . . . , PWM n). As a result of having to generate the plurality of pulse modulation signals (PWM 1, PWM 2, . . . , PWM n), the engine controller 10 is greatly burdened.
Additionally, if the image forming apparatus connected to the conventional high voltage power supply 100 or another output load such as the development device 50 is changed, the high voltage output(s) is also changed. Therefore, a re-tuning of a high voltage outputs (HV output 1, HV output 2, . . . , HV output n) is required to output constant high voltage output(s). The high voltage output(s) change according to the output load.
The high voltage output(s) of the conventional high voltage power supply 100 should be set by using a variable resistance in an offline setting, and then be mounted to the image forming apparatus so that it is determined whether the high voltage output(s) having the set value is output. Once this process is completed, the conventional high voltage power supply 100 can be manufactured. Therefore, time and complication for manufacturing the conventional high voltage power supply 100 are costly.